A flow cell 100 used for a conventional particle measuring apparatus as shown in FIG. 6(a) is made of a transparent member, and provided with a linear passage 100a having a predetermined length, the cross-sectional shape of which is rectangular. Also, the shape of the flow cell is an L-shaped tube as a whole. The central axis of the linear passage 100a substantially corresponds with the axis of receiving scattered light Ls by a condenser lens system 101 (See Japanese Patent Application Publication No. 11-211650). Incidentally, reference number 102 refers to a laser light source, and reference number 103 refers to a photoelectric transducer element.
In the flow cell 100 used for a conventional particle measuring apparatus, inner walls b, c, d, and e disadvantageously limit the path of light scattered Ls by particles passing through a particle monitoring area M, and the condensing angle of the condenser lens system 101 cannot be fully utilized.
Contrary to the conventional apparatus, if the level of detecting scattered light, and hence the accuracy of detecting particles, is to be improved, it is necessary to fully utilize the condensing angle of the condenser lens system 101.
The present invention was made to solve the above-mentioned drawbacks, and the object of the present invention is to provide a flow cell which can detect scattered light more efficiently by fully utilizing the condensing angle of a condenser means, and also a particle measuring apparatus using the flow cell.